1. Field of the Invention
The present invention relates to an electronic timepiece having a function of generating electricity.
2. Description of the Related Art
Electronic timepieces having various types of electricity generation functions have been implemented, for instance, solar powered timepieces, thermo-electrically powered timepieces, and quasi-self-winding timepieces, the latter converting the kinetic energy imparted by movement of a timepiece into electricity. By storing the generated electricity in a secondary battery for utilization later, such timepieces can operate even when electricity is not being generated.
If, in an electronic timepiece having an electricity generation function and a secondary battery, the secondary battery continues to discharge without electricity being generated, when generation of electricity eventually does occur, a long time is required for the output voltage of the secondary battery to recover. During this time, the timepiece remains stopped.
Hence, there exists a quick-start technique of adding a small auxiliary capacitor to the secondary battery, to quickly start the timepiece by charging the auxiliary capacitor and using the voltage thereof.
There also exists a technique (called a zero-reset), for a needle electronic timepiece, of stopping hands at a predetermined position before exhaustion of the secondary battery stops the timepiece, so that the position of the hands may not be lost when the power supply voltage recovers.